Method of protecting plants against arachnids with xanthates



United States Patent Claims. (cl. 167-30 The invention relates tocompositions for combating arthropoda, and in particular insects andspiders and more in particular mites, characterized by a content of acompound of the formula in which formula R is an alkyl group having 1 to12 and preferably 2 to 6 carbon atoms or an alkoxyalkylene group having1 to 12 and preferably 3 to 6 carbon atoms, as an active'ingredient.

Applicants have found that compositions according to the invention arealso active against red spider which are resistant against knowncombating agents, for example,0,0-diethylO-4-nitropheny1-thionophosphate. This unexpected property ofthe compositions may be of great importance becausethe phenomenon ofresistance of insects and of mites, and, for example, of red spider,occurs more and more.

To the most active compositions according to the invention belong thosewhich contain as an active ingredient the benzyl ester of ethyl-,butyl-, n-hexyor methoxyethylene xanthogenic acid and in particularthose comprising O-n-butyl-S-benzyl xanthate or O-n-hexyl-S-benzylxanthate as an active ingredient. Other examples of active ingredientsare: O-isobutyl-S-benzyl xanthate, O-isoamyl-S-benzyl xanthate,O-methylisobutyl-S-benzyl xanthate, O-Z-ethylhexyl-Sbenzyl xanthate andO-n-dodecyl- S-benzyl xanthate. The compositions are-in particularactive against eggs of the red spider. This has appeared in particularin experiments on eggs .of the type T etranychus urticae Koch.

The preparation of a composition according to the invention may becarried out according to a manner known for such an agent or mannersanalogous thereto.

A dust may be prepared, for example, by grinding 2 parts by weight ofthe active ingredient, 12 parts by weight of chalk and 80 parts byweight of dolomite until an average particle size of approximatelymicrons is obtained.

A wettable powder may be prepared, for example, by mixing parts byweight of the active ingredient, 75 parts by weight of attapulgite, 2parts by weight of oleylamidomethyltaurate and'3 parts by weight ofsodium lignine sulphonate, and grinding until an average particle sizeof approximately 10 microns is obtained.

A miscible oil may be prepared, for example, by mixing I kaolin orpipeclay; for the preparation ,of miscible oils,

3,183,144 Patented May 11, 1961 other inert diluents may be used, forexample, benzem toluene or cyclohexanone. Surface-active substances othethan those mentioned may also be used.

The activity of compositions according to the inventio was determined iein house flies (M usca domestic), blac fiies- (Ap/zis fabae Scop.) andred spider (Tetranycha urticae Koch). To plants which were infected withre spider and eggs thereof a dust consisting of 2 parts b weight ofO-isobutyl-S-benzylxanthate and 98 parts b weight of pulverized chalkwas applied. Already with very low dose, 100% killing was reached.

A similar experiment was carried out on plants whic were infected withthe black fly.

The activity on fruit red spider on apple was detel mined in experimentsin which a composition according't the invention in the form of adispersion-obtained b dispersing 5 g. of a wettable powder, consistingof509 of kaolin, 2% by weight of oxylamido-methyltanrate an 3% by weightof sodium lignin sulfonate, in 101 o water-was sprayed on apple treesinfected with frui red spider. With a very low .dose, complete killingofth red spider was reached.

What we claim is:

1. A method of protecting living plants against ara'cl: nids comprisingtreating said plants with a benzyl xa: thate of the formula:

wherein R is a member selected from the group cor sisting of alkyl of112 carbon atoms and alkoxylalkylen of 1 to 12 carbon atoms.

2. A method of protecting living plants against aracl nids comprisingtreating said plants with a benzyl xar thate of the formula:

n-o-cs-s-cm-Q wherein R is alkyl of 2-6 carbon atoms.

3. A method of protecting living plants against aracl nids comprisingtreating said plants with a benzyl xar thate of the formula:

wherein R is alkoxyalkylene of 3 to 6 carbon atoms.

4. A method of protecting living plants against aracl nids comprisingtreating said plants with O-n-butyl-E benzyl xanthate.

5. A method of protecting living plants against aracl nids comprisingtreating said plants with O-n-hexyl-E benzyl xanthate;

References-Cited by the Examiner UNITED STATES PATENTS 2,859,561 6/58Schrader 167-3 2,861,913 11/58 Wegler et al. l673 OTHER REFERENCES Chem.Abst., vol. 55; 1961', p. 27179.

S. Primary Examiner. FRANK ,caocIAPAoLIA, 1a., Examiner.

1. A METHOD OF PROTECTING LIVING PLANTS AGAINST ARACHNIDS COMPRISING TREATING SAID PLANTS WITH A BENXYL XANTHATE OF THE FORMULA: 